Common practice in ordnance systems is the desirable employment of squibs, detonators and other electroexplosive devices to provide the thermal and/or shock stimulus that causes ignition or explosion of adjacent pyrotechnics or explosives. Such materials are frequently used in a train or in series of events that ultimately provides ignition of rockets for military or space applications. Electroexplosive devices commonly employ a metal wire filament surrounded by pyrotechnics or explosive materials. Upon application of voltage, the filament is heated or caused to vaporize (even with explosive violence, depending on firing circuit employed) and the immediately surrounding material is ignited, or caused to explode or detonate. This output either directly ignites the next element in the ignition train or leads to the formation of a shock wave that initiates detonation.
However, electroexplosive devices are generally vulnerable, in various degrees, to electromagnetic radiation fields, electrostatic discharge, cookoff, impact, and other extraneous energy sources that can directly or indirectly initiate the active chemical material in direct contact with, or in the immediate vicinity of the metal wire filament or bridgewire. For example, handling of certain rocket weapons on Navy ships is prohibited when their high powered radar equipment is turned on, because of extreme vulnerability of the squibs in the igniters.
Thus, the current state of the art method of providing electrical initiation of igniters containing explosives inherently include various degrees of vulnerability which must be considered in the environment of use.
Desirable would be a device which is very safe for normal handling, exposure to strong electromagnetic fields, and electrostatic discharge, and yet a device which has the capability to initiate rocket igniters and other ordnance. Very desirable would be a device which does not contain any explosive or pyrotechnic material, but which has the capability to initiate rocket igniters and other ordnance.
The primary object of this invention is to provide a device which does not contain any explosive or pyrotechnic material but a device which has the capability to initiate rocket igniters and other ordnance.
Another object of this invention is to provide a device which functions in conjunction with a small diameter nonelectric shock transfer tube to produce shock waves which are normally produced by explosive percussion primers, blasting caps, detonators, or brisant squibs for initiating rocket igniters and other ordnance.